Chemistry Year 11 - Module 2 - Lesson 1

The Mole Concept

Use this worksheet after reading the lesson to practise the key ideas and prove you can meet the success criteria.

Name
Date
Class

1. Key Ideas

A dozen means 12. A century means 100. A mole means 602,200,000,000,000,000,000,000. Chemists chose this number for a very specific reason — and once you understand why, every calculation in this module falls into place.

  • What a mole is and why it exists
  • How Nₐ bridges atomic and lab scales

2. Success Criteria

By the end, you should be able to:

  • What a mole is and why it exists
  • Avogadro's number and its units
  • The difference between N and n

3. Key Terms

MoleThe SI unit for amount of substance; contains exactly 6.022 × 10²³ particles.
Avogadro's Number6.022 × 10²³ — the number of particles in one mole of a substance.
Molar MassThe mass of one mole of a substance, measured in g/mol.
Limiting ReagentThe reactant that is completely consumed first, limiting the amount of product formed.
Empirical FormulaThe simplest whole-number ratio of atoms in a compound.
Molecular FormulaThe actual number of atoms of each element in a molecule of a compound.

4. Activity: Build the Lesson Map

Use the lesson to complete the table. Keep answers brief but specific.

PromptYour answer
Main concept
Important example
Common mistake to avoid
How this links to the next lesson

5. Short Answer Questions

1. Explain this lesson goal in your own words: "What a mole is and why it exists". Use one specific example from the lesson.

Band 32 marks

2. Apply this idea to a new example: "Avogadro's number and its units". Show your reasoning clearly.

Band 43 marks

3. Analyse why this idea matters for understanding The Mole Concept: "The difference between N and n".

Band 54 marks

6. Extend: Apply the Idea

Band 5/65 marks

A student gives a memorised answer about The Mole Concept but does not use evidence or reasoning.

Improve the answer by writing a stronger response that uses accurate terminology, a relevant example and a clear explanation.

7. Multiple Choice

1. What is the best first step when answering a question about The Mole Concept?

A. Identify the key concept being tested

B. Write every fact from memory

C. Ignore the command word

D. Skip examples and evidence

2. Which answer would show stronger understanding of The Mole Concept?

A. An answer with accurate terms and reasoning

B. A copied definition only

C. A single-word response

D. An answer with no example

3. What should you do if a question asks you to explain?

A. Link the idea to a reason or cause

B. List unrelated facts

C. Only draw a diagram

D. Write the shortest possible answer

8. Success Criteria Proof

Finish with evidence that you can do each success criterion.

Success criterion 1

Prove that you can: What a mole is and why it exists

Band 32 marks
Success criterion 2

Prove that you can: Avogadro's number and its units

Band 43 marks
Success criterion 3

Prove that you can: The difference between N and n

Band 54 marks

One thing I still need help with: